1. Field of the Invention
The present invention relates generally to a self-gripping flexible rack for stacking articles such as propane tanks and more particularly to a self-gripping flexible rack having a flexible strap extending around the rack holder body.
2. Description of the Background Art
Various types of racks are known for stacking and transporting articles such as propane tanks. With their round configuration, it is difficult to transport a number of large tanks due to legal limitations on the size of the truck. In addition, the racks may be heavy and bulky, thus taking up additional space and adding an extra load to the truck, leading to increased fuel usage. It is also often necessary to use a crane or multiple people to place the rack on the truck, leading to increased costs.
U.S. Pat. No. 5,735,412 describes a rack system which is a major improvement over prior art systems. In this rack system, a pair of holders, each having curved sides to match the shape of the propane tank, are joined by a flexible strap. The strap acts as a seat for an additional tank placed between the original two tanks onto which the holders are placed. Because of the small size of the holders and strap, it is possible to carry additional tanks on the same size truck. The weight of such rack is considerably less than prior art systems, which reduces the weight on the truck and allows for easy installation by a single person. In this system, the strap is connected to the holder by sewing the end of the strap to make a loop and inserting a bolt through the holder and the loop to fasten it in position. In order to prevent any damage to the paint on the tanks, pads are placed along the contacting surfaces of the holders.
While this system was a major improvement over prior art devices, the placing of the pads requires considerable time, using skilled labor and laboratory conditions to install. When pads wear out and need to be replaced, it is necessary to sand the metal to acquire a clean surface. As a result, the metal parts must be relatively thick so that multiple sandings do not reduce the strength of the holder. The holders must then be heavier than would otherwise be necessary. The loop formed by sewing the end of the strap is weaker than the other parts of the system and accordingly limits the amount of weight the system can hold. Also, the operations of sewing a strap and inserting a bolt require a certain amount of time and cost.